Charles ellis



@uitrit --tats `htttrittl ffice;

Letters Patent No. 76,612, olateoZjprz'l 14, 1868. 4

IMPROVEMENT 11N 'SCREW-CUTTING Lamas.

@its .rlgrhult referat it' in time tettet rtuit mit mating tutti thearms.

`To ALL WHOM 1T' MAY ooNeERN;

Be it'known that I, CHARLES ELLIS, of Canton,- inth'e county of Norfolk,and State of Massachusetts, have invented a new and useful Improvementin Lathes for Cutting Screws; aud I do hercbydeclare the following to bea full, clear, and exact description of the same, reference being' hadtothe accompanyingdrawings, making a part of this specication, in which-Figurel is a front elevation of a lathe embodying my invention.

Figure 2 is a plan of the same.

Figure 3 is an end elevatom Y Figure 4 is a vertical longitudinalsection through the axis of the chuck.

Figure 5 is a transverse section on line x :v of iig. 4. l l

The object of my invention is to facilitate the cutting of thescrew-threads on the ends of carriage-ailles, and other similaroperations, and consists- A f l First. In the applicationof twoself-centring chucks arranged on ahollow spindle, in such 'a manner thatboth may be. brought to bear upon the object to be centred, at pleasure.A I

Second. In the application of a third chuck, not self-centring, buthaving itsl jaws so arranged that they may b`e operated independentlyvofeach other, so 'that they may be adjusted to bear upon the rough orunfinished portion of the `axle to clamp the same, whether it bestraight or crookedpand'its contact with the axle to insure itsrevolution, without danger of defacing the surface of the finishedportion of the axle on'which the self-centring' chucks act.v

Third. In the use, in combination with the above-mentioned centi-ing andholding-chucks, ofa revolving p die-holder; and

Fourth. In the use, in combination with the abovemen`tioned centring andholding-chucks and revolving die-holder, of a tool-post and carriage, soarranged that, when the axle is secured in the hollow spindle of theheadstock, the axle may be operated upon by the turning-tool, and thescrew cut on it without removing it from the lathe. l

In thc drawings, is the bed ofv the lathe, made in the usual form. 'Band B are stands,lbolted to the bed at or near one end, and serving thepurposey of a head-stock to support the hollow spindle C and C. D and Dare two self-centring chucks, mounted on the hollow spindle C, and madefast to it, so as to revolve with it. These chucks consist of circulardisks, provided with4 dove-tailed grooves across their faces, in alineatY right angles to the laxis of their revolution, into which are fittedthe jaws E and E and F. These jaws are operated by means of the screws Gand G', provided with right and left-hand threads, working incorresponding right and left-hand threads cut in the jaws.V Said screwsare provided with the adjusting-nuts or collars a and and the chuck-nutsc and d, by means of which the jaws in .the chuck may be accuratelyadjusted, so that the centrebetween the two jaws shall exactly coincidewith the airis of the chucks.

The screws are operated by the crank-wrench H. I is -a thirdchuck,.mounted Von and made-fast to the hollow spindle-Cf, and providedwith jaws J and J?, similar inform to those -in vthefcentringfchucks Dand D but operated independently of each other, by means of the screws KandK'. L is a spurg'ear, also mounted on andmade fast to the spindle C',and also bolted'rmly to the centring-chuck D', so that the two hollowspindles C and C are .thereby .rigidly connected, and become in Aeffectone hollow spindle. n

i Mis the revolving die-holder, mounted on the column N, and fitted tomove on the slides of the lathe-bed,

and is fed to the work by meausof the hand-crank O and the pinion Pworking in the rack Q. 'The dic-holderis held in position bymeans of therigid 'arm'R andl pin S'. T is the die, and each face of the die-holdermay be'provided with a die of a different style or size, and adapted todojthe various kinds of work desired.

U is the ordinary tool-carriagefor turning oil` the end of the axle andthe nut, arid is fedv to the work in y the same manner as thedie-holder.

ngen 2 The chucks are driven by the pinion V on the driving-shaft W,supported in the bearings XIX. On the.

outer end of this shaft will be placed the driviug-pulleyfin the placeof the crank Y'shown in the drawings.

AlthougbI have shown the above mode of driving the chucks, they may bedrivenin any other well-known way. The operation of, my machinel is asfollows: The axle is placed in the hollowepindle, when the `jaws of thecentring-cllucks D and D are Adra-wn towards each other, by revolvingthe screwsG -and G', soA that they grasp the turned portion of the axle,and bringthe centre of the axle to coincide with the axis ofrevolution.l

When this has been done, the jaws of the holding-chuck I are then set upto the axle, by turning the screws K and K', when it is ready .to beoperated upon, by the vturning-tool or the die, at the pleasure oftheoperator.

The work of turning and cutting the screw does not differ materiallyfrom common practice, and need notbe described. i l

I am aware that a'self-centring chuck, with a single set of jaws, hasbeen heretofore used,'and therefore do not claim it as such; but

Wliat I claim as my invention, and wish to secure by Letters Patent, is-4 1. The holding-chuck, in combinationwith the self-centringchucks,substantially as described.

2. 'The combination of the self-centring chucks D and D', theholding-chuck I, andthe revolving die-holder M, substantially asdescribed. v

3. Th'combination of the chucks D and Dand I, the revolving die-holderM, and the tool-carriage Uwhen made substantially as described and forthe purpose specified.

4. ,The adjusting-collars a and band right and left screws G AGr,'incombination with the slidixrg jaws of a chuck, so that the said jawsshall always` have their corresponding faces at an equal distance fromthe centi-e of revolution. I

5. The employment, in combination with the right and left `screws G G',of the adjustable collars`a b, by which the'jaws are centred,substantially as described.

Executed at Boston, this'itbrteentb day of November, 1867.

` CHAS. ELLIS.

Witnesses: l

N. C. LOMBARD, CnAs.'A. JORDAN.

